JP6606842B2 - Method for producing resin particle dispersion and method for producing toner particles - Google Patents

Description

  The present invention relates to a method for producing a resin particle dispersion and a method for producing toner particles.

In Patent Document 1, a resin is melt-mixed in the absence of an organic solvent, a surfactant is added to the resin as necessary, and a basic agent and water are added to the resin. Forming an emulsion of particles, and a method of making the emulsion is disclosed.
Further, in Patent Document 1, the basic agent is selected from the group consisting of ammonium hydroxide, potassium hydroxide, sodium hydroxide, sodium carbonate, sodium hydrogen carbonate, lithium hydroxide, potassium carbonate, organic amines, and combinations thereof. It is disclosed that it is selected.
In addition, Patent Document 1 describes that a surfactant is optionally added before, during, or after melt mixing of the resin at a high temperature, but a specific prescription is shown. Not.

  In Patent Document 2, at least one polyester resin having at least one acid group is prepared in a reaction vessel, and the resin is brought into contact with a specific base to neutralize the at least one acid group. Contacting the neutralized resin with at least one surfactant in the absence of a solvent emulsifies the neutralized resin to provide a latex emulsion containing latex particles, the latex particles being continuously A method for producing latex particles is disclosed, characterized in that it comprises a step of automatically recovering.

  Patent Document 3 discloses a method for producing a latex emulsion by a continuous solvent-free emulsification process, which is performed on a supply hopper of a screw-type extruder having a screw that is driven to rotate along a path by a drive shaft. Feeding the material at a controlled rate, melting the material by dissipative mixing within the path of the screw extruder, and injecting a first amount of water into the melted and mixed material Mixing the material with a kneading member having a first series of one or more feed blades, non-moving blades, return blades, injecting a second amount of water, A method for producing a latex emulsion is disclosed which comprises applying a series of kneading members and recovering a colloidal dispersion from the outlet of the screw extruder.

Patent Document 4 discloses that a pre-blended mixture is prepared by optionally contacting at least one amorphous polyester resin and an optional plasticizer, and the pre-blended mixture is neutralized with a neutralizing agent. Creating a neutralized pre-blended mixture; contacting the neutralized pre-blended mixture with a surfactant selected from alkyl sulfates, alkyl ether sulfates, or combinations thereof; and pre-blending A process for producing a latex comprising: melt-mixing the resulting mixture; contacting the melt-mixed mixture with deionized water to form an oil-in-water emulsion containing the latex; and recovering the latex. It is disclosed.
That is, Patent Document 4 discloses that a mixture obtained by previously blending an amorphous polyester resin and a plasticizer is neutralized with a neutralizing agent, and the neutralized pre-blended mixture is brought into contact with a surfactant.

  In Patent Document 5, a mixing step of mixing at least an aqueous medium, a polyester resin and a surfactant to obtain a mixture, when the glass transition point of the polyester resin is Tg (° C.) and the softening temperature is Tm (° C.), A neutralization step in which the pH of the mixture is 6.0 or more and 8.5 or less while heating at a temperature T1 (° C.) of Tg or more and Tm or less, and the mixture after the neutralization step is T1 or more. Resin fine particles having an emulsification step in which an emulsion is obtained by applying a shear force while heating at a temperature T2 (° C.), and a cooling step in which an aqueous dispersion of resin fine particles is obtained by cooling the emulsion while applying a shear force A method for producing an aqueous dispersion is disclosed.

  Patent Document 6 discloses a mixing step of mixing at least a binder resin and a colorant to obtain a toner raw material mixture, a melt kneading step of melting and kneading the toner raw material mixture to obtain a melt kneaded product, A coarse pulverization step of pulverizing to obtain coarse pulverized particles having a volume average particle diameter of 0.5 to 5 mm, and an aqueous medium is added to the coarsely pulverized particles to perform phase inversion emulsification, and the volume average particle diameter is 0.1 to 2 μm. A fine particle dispersion preparing step of preparing a fine particle dispersion in which colored resin fine particles are dispersed in an aqueous medium, and an aggregating step of aggregating the colored resin fine particles contained in the fine particle dispersion to obtain a dispersion of toner base particles. A method for producing a toner containing the toner is disclosed.

JP 2009-191271 A JP 2009-237572 A JP 2011-240334 A JP 2012-155322 A JP 2012-159805 A JP 2010-210957 A

  The problem of the present invention is that the weight average of the polyester resin is compared with the case where an ionic surfactant and an aqueous medium are added to the melt-kneaded mixture after the polyester resin is neutralized by mixing with an alkali agent and melt-kneaded. It is an object of the present invention to provide a method for producing a resin particle dispersion capable of controlling the molecular weight.

  The above problem is solved by the following means. That is,

<1>
A melt-kneading step of melt-kneading a mixture of the polyester resin and the ionic surfactant;
An addition step of adding an alkali agent and an aqueous medium to the melt-kneaded mixture to obtain a resin particle dispersion in which the polyester resin particles are dispersed in the aqueous medium;
It is a manufacturing method of the resin particle dispersion which has this.

<2>
The weight average molecular weight of the polyester resin is a method for producing a resin particle dispersion according to <1> , which is from 40,000 to 100,000.

<3>
The said polyester resin is a manufacturing method of the resin particle dispersion as described in <1> or <2> formed by bridge | crosslinking with the crosslinking component which has a 3 or more functional group.

<4>
In the melt-kneading step and the adding step, the mixture is melt-kneaded while flowing the mixture from one end to the other end in the cylindrical body, and the alkali agent and the aqueous medium are added to the melt-kneaded mixture. a step of a manufacturing method of the resin particle dispersion liquid according to any one of <1> to <3>.

<5>
The alkaline agent is a process for the preparation of containing silicate <1> to the resin particle dispersion liquid according to any one of <4>.

<6>
<1> by any method for producing a resin particle dispersion liquid according to one to <5>, particles of the polyester resin to produce a resin particle dispersion prepared by dispersing in an aqueous medium, a resin particle dispersion production step,
In the resin particle dispersion, the polyester resin particles are aggregated to form aggregated particles including the polyester resin particles, and an aggregated particle forming step;
A fusion / union step of heating the aggregated particle dispersion in which the aggregated particles are dispersed in the aqueous medium, and fusing and coalescing the aggregated particles to form toner particles;
A method for producing toner particles having

According to the invention according to <1> , the polyester resin is neutralized by mixing an alkali agent, melt-kneaded, and then added to an ionic surfactant and an aqueous medium in the melt-kneaded mixture. A method for producing a resin particle dispersion capable of controlling the weight average molecular weight of a resin is provided.
According to the invention according to <2> , even if a polyester resin having a weight average molecular weight of 40,000 or more and 100,000 is used, the polyester resin is neutralized by mixing with an alkali agent and melt-kneaded, and then the mixture is ionic. As compared with the case where a surfactant and an aqueous medium are added, a method for producing a resin particle dispersion capable of controlling the weight average molecular weight of a polyester resin is provided.
According to the invention according to <3> , even when using a polyester resin crosslinked with a crosslinking component having three or more functional groups, the polyester resin is melt-kneaded after being neutralized by mixing with an alkali agent and melt-kneaded. In addition, a method for producing a resin particle dispersion capable of controlling the weight average molecular weight in a polyester resin is provided as compared with the case where an ionic surfactant and an aqueous medium are added to the mixture.
According to the invention which concerns on <4> , compared with the case where a melt-kneading process and an addition process are performed batchwise, the manufacturing method of the resin particle dispersion liquid which can control the weight average molecular weight in a polyester resin is provided.
According to the invention which concerns on <5> , compared with the case where only sodium hydroxide is used as an alkali agent, the manufacturing method of the resin particle dispersion liquid which can control the weight average molecular weight in a polyester resin is provided.
According to the invention according to <6> , in the production of the resin particle dispersion, an ionic surfactant and an aqueous medium are added to the melt-kneaded mixture after the polyester resin is neutralized by mixing with an alkali agent and melt-kneaded. As compared with the case of adding the toner, a method for producing toner particles capable of controlling the weight average molecular weight of the polyester resin is provided.

It is a schematic block diagram which shows an example of the screw extruder used for manufacture of the resin particle dispersion which concerns on this embodiment.

  Hereinafter, an embodiment which is an example of the present invention will be described in detail.

<Method for producing resin particle dispersion>
The method for producing a resin particle dispersion according to this embodiment includes a melt-kneading step of melt-kneading a mixture of a polyester resin and an ionic surfactant, and adding an alkali agent and an aqueous medium to the melt-kneaded mixture. And an addition step of obtaining a resin particle dispersion in which the polyester resin particles are dispersed in the aqueous medium.
In the method for producing a resin particle dispersion according to the present embodiment, the ionic surfactant and the aqueous medium are added to the melt-kneaded mixture after the mixture of the polyester resin and the alkali agent is melt-kneaded because of the above configuration. As compared with the case of adding a resin, a resin particle dispersion capable of controlling the weight average molecular weight of the polyester resin is obtained.
The reason why the above effect can be obtained is presumed as follows.

  As one method for obtaining a polyester resin particle dispersion, for example, a mixture of a polyester resin and an alkali agent is melt-kneaded in order to impart emulsifying properties by neutralizing the acid chain terminal acid groups, and then the molten mixture. And a method of emulsifying and dispersing by adding a surfactant and an aqueous medium. However, in the above method in which the polyester resin and the alkali agent are directly mixed at a high temperature, the polyester resin is likely to be hydrolyzed, so that a polyester resin particle dispersion having a relatively low weight average molecular weight is easily obtained. In addition, a polyester resin having a structure crosslinked with a component having three or more functional groups is likely to cause a decrease in molecular weight even when exposed to a meltable high temperature for a short time. The preparation of was difficult.

On the other hand, in this embodiment, after mixing a polyester resin and an ionic surfactant and melt-kneading in advance, an alkali agent is added to the molten mixture. Therefore, the ionic surfactant is present in the vicinity of the polyester resin, and in addition to the resin chain and the alkali agent being difficult to come into direct contact, the alkali agent has an action of enhancing the emulsifying function of the ionic surfactant. Thus, it is presumed that the emulsification / particulation of the polyester resin is promoted and the resin particles are easily formed. In addition, in this embodiment, since the polyester resin is easily plasticized by mixing the polyester resin and the ionic surfactant first, the viscosity is lowered at a lower temperature than when the resin alone is heated and melted, and the same temperature. Then, an alkali agent is added to the polyester resin in a lower viscosity state. Therefore, compared to the case where an alkali agent is added to a high-viscosity polyester resin alone such as a high molecular weight substance, the alkali agent is easily adapted and dispersed in the resin layer. It is thought that it is hard to happen to act on. In addition, by ionic surfactant in advance good dispersing, in a state where capture and dispersibility was also improved alkaline agent and water medium. For the above reasons, it is presumed that in this embodiment, the polyester resin is hardly hydrolyzed by the alkali agent, and a resin particle dispersion capable of controlling the weight average molecular weight in the polyester resin is obtained.

In particular, even when using a polyester resin having a weight average molecular weight of 40,000 or more and 100,000 or less or a polyester resin crosslinked with a crosslinking component having three or more functional groups, according to the method for producing a resin particle dispersion of this embodiment, since hydrolysis Ru is suppressed by the above reasons, the resin particle dispersion capable of controlling a weight average molecular weight is obtained.
Further, polyester resins having a weight average molecular weight of 40,000 or more and 100,000 or less and polyester resins crosslinked with a crosslinking component having three or more functional groups have a high temperature (melting temperature) at which the resin softens and becomes a fluid state by heating. (For example, 130 ° C. or higher) in many cases. As described above, a resin having a high melting temperature is likely to cause a decrease in molecular weight when exposed to a temperature at which it can be melted alone, and is unlikely to be in a sufficiently molten state at a temperature that does not easily cause a decrease in molecular weight. It tends to be in a highly viscous state. However, in this embodiment, since the polyester resin is easily plasticized by first mixing with the ionic surfactant, the polyester resin is more polyester than the case where the resin alone is heated and melted even at a temperature at which the molecular weight is not easily lowered. The resin has a low viscosity. And by adding an alkali agent and an aqueous medium to a mixture of a polyester resin and an ionic surfactant in a low-viscosity state at a temperature at which the molecular weight is not easily lowered by the resin alone, hydrolysis is suppressed as described above. Thus, a resin particle dispersion having a controlled weight average molecular weight can be obtained.
Examples of the crosslinking component having three or more functional groups include at least one of a trivalent or higher carboxylic acid and a trivalent or higher polyhydric alcohol described below.

  In the present embodiment, in the melt-kneading step and the adding step, it is preferable to melt-knead the mixture while flowing the mixture from one end to the other end in the cylindrical body, and add the alkali agent and the aqueous medium to the molten mixture. Hereinafter, in the melt-kneading step and the addition step, the mixture is melt-kneaded while flowing the mixture from one end to the other end in the cylindrical body, and an alkali agent and an aqueous medium are added to the melt-kneaded mixture as “fluid addition” Sometimes referred to as the "law". In the form to which the fluid addition method is applied, since the alkali agent is added by melting and kneading while flowing the mixture, uneven distribution of the alkali agent is suppressed, and hydrolysis of the polyester resin by the alkali agent is less likely to occur. Thereby, it is presumed that a resin particle dispersion capable of controlling the weight average molecular weight in the polyester resin can be obtained as compared with the case where the melt-kneading step and the adding step are performed batchwise.

  In this embodiment, it is preferable to use an alkali agent containing silicate as the alkali agent. In this embodiment, an alkali agent is used as an auxiliary agent for the ionic surfactant. Therefore, by using a silicate suitable as an auxiliary for an ionic surfactant as an alkali agent, for example, only a strong alkali such as sodium hydroxide suitable for the purpose of neutralizing the acidic group of the resin is used as the alkali agent. Compared with the case where it was, the function of an ionic surfactant becomes easy to be activated. In addition, by using a silicate having a lower alkalinity than sodium hydroxide as an alkaline agent, hydrolysis of the polyester resin by the alkaline agent is less likely to occur than when only sodium hydroxide is used as the alkaline agent. From these facts, it is speculated that when an alkali agent containing silicate is used, a resin particle dispersion capable of controlling the weight average molecular weight in the polyester resin can be obtained compared to the case where only sodium hydroxide is used as the alkali agent. Is done.

  Moreover, in this embodiment, since an alkali agent is used as an auxiliary agent for the ionic surfactant, for example, the amount of the alkali agent added is generally required for a technique for neutralizing the terminal acidic group of the resin and imparting emulsifying properties. In comparison, the resin particle dispersion can be formed even with a small addition amount of the alkali agent. In addition, since the addition amount of the alkali agent is small, the polyester resin is hardly hydrolyzed by the alkali agent, and a resin particle dispersion having a controlled weight average molecular weight in the polyester resin can be obtained.

Hereinafter, the manufacturing method of the resin particle dispersion using the screw extruder shown in FIG. 1 is demonstrated as an example of the form which applied the said fluid addition method among the manufacturing methods of the resin particle dispersion of this embodiment.
Examples of the screw extruder include a single screw extruder and a twin screw extruder, and a twin screw extruder is preferable from the viewpoint of the kneading effect.

  A screw extruder 11 shown in FIG. 1 includes a barrel 12 (an example of a cylindrical body) provided with two screws (not shown), and an injection nozzle 14 for injecting a polyester resin and an ionic surfactant into the barrel 12. And a liquid addition port 16A for adding an alkaline agent and an aqueous medium to the mixture of the polyester resin and the ionic surfactant in the barrel 12, and further adding an aqueous medium to the mixture to which the alkaline agent and the aqueous medium are added. The liquid addition port 16B and the liquid addition port 16C for performing the above and the discharge port 18 for discharging the resin particle dispersion formed in the barrel 12 are configured.

The barrel 12 includes a melt kneading part SA for melting and kneading a mixture of the polyester resin and the ionic surfactant injected from the injection nozzle 14 in order from the side closer to the injection nozzle 14, and an alkali agent and It is divided into an addition part SB for adding an aqueous medium to form a resin particle dispersion and a discharge part SC for transporting the formed resin particle dispersion to the discharge port 18.
The barrel 12 is provided with temperature control means (not shown) that is different for each block. That is, the temperature may be controlled at different temperatures from the block 12A to the block 12J. The number of blocks is limited by the length of the shaft, but can be changed within a range corresponding to the apparatus.

  In the method for producing a resin particle dispersion using the screw extruder 11 shown in FIG. 1, the melt-kneading process is performed in the melt-kneading part SA of the barrel 12, and the adding process is performed in the adding part SB of the barrel 12. Hereafter, the manufacturing method of the resin particle dispersion using the screw extruder 11 shown in FIG.

-Melt kneading process-
In the melt kneading step, a mixture of the polyester resin and the ionic surfactant is melt kneaded. Specifically, for example, a polyester resin and an ionic surfactant are charged into the injection nozzle 14 of the screw extruder 11 shown in FIG. The polyester resin and the ionic surfactant supplied from the injection nozzle 14 to the barrel 12 are fed from the block 12A of the barrel 12 to the block 12B while being melt-kneaded by the screw in the barrel 12.
The polyester resin and the ionic surfactant are mixed with each other by melt-kneading the mixture in the melt-kneading step.
The polyester resin and the ionic surfactant may be mixed directly into the injection nozzle 14 in a fine powder state, or the ionic surfactant and an aqueous solution thereof may be added to the polyester resin in a powder or pellet form. A mixed or moist state may be added. Further, a polyester resin and an ionic surfactant previously melt-kneaded to be homogenized may be pulverized into powder.

As a polyester resin, a well-known polyester resin is mentioned, for example, 1 type may be used independently and 2 or more types may be used together.
As a polyester resin, the condensation polymer of polyhydric carboxylic acid and polyhydric alcohol is mentioned, for example. In addition, as a polyester resin, a commercial item may be used and what was synthesize | combined may be used.

Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (for example, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.) , Alicyclic dicarboxylic acids (for example, cyclohexanedicarboxylic acid), aromatic dicarboxylic acids (for example, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), anhydrides thereof, or alkyl esters thereof. Among these, as polyvalent carboxylic acid, aromatic dicarboxylic acid is preferable, for example.
The polyvalent carboxylic acid may be used in combination with a dicarboxylic acid or a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, anhydrides thereof, and lower (for example, having 1 to 5 carbon atoms) alkyl esters. Can be mentioned.
Polyvalent carboxylic acid may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol include aliphatic diols (for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (for example, cyclohexanediol, cyclohexanedimethanol, Hydrogenated bisphenol A, etc.) and aromatic diols (for example, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, as the polyhydric alcohol, for example, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable.
As the polyhydric alcohol, a trihydric or higher polyhydric alcohol having a crosslinked structure or a branched structure may be used together with the diol. Examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolpropane, and pentaerythritol.
A polyhydric alcohol may be used individually by 1 type, and may use 2 or more types together.

  The glass transition temperature (Tg) of the polyester resin is preferably 50 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 70 ° C. or lower. The glass transition temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC), and more specifically, described in the method for determining the glass transition temperature in JIS K-1987 “Method for Measuring Transition Temperature of Plastics”. It is determined by “extrapolated glass transition start temperature”.

Examples of the weight average molecular weight (Mw) of the polyester resin include 1500 to 1000000. Among them, for example, when the obtained resin particle dispersion is used for the production of toner particles, it is 1500 to 100000. Is preferred. In the present embodiment, a polyester resin having a weight average molecular weight (Mw) of 1500 or more and 40000 or less can also be applied, and a resin particle dispersion with a controlled molecular weight can be obtained. It is preferably 1000000 or less, more preferably 7000 or more and 500000 or less, and particularly preferably 40000 or more and 120,000 or less.
In general, the resin in the molecular weight region that is more effective is more resistant to heat, acid, and alkali. However, for example, a molecule with a structure having a cross-linking point or a side chain with a large number of carbon atoms decomposes into the molecular chain. Because it has a part that is easy to do, it is suitable for applying this measure.
The weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is carried out with a THF solvent using a Tosoh column / TSKgel SuperHM-H (15 cm) using a Tosoh GPC / HLC-8120GPC as a measuring device. The weight average molecular weight and the number average molecular weight are calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample from this measurement result.
The weight average molecular weight of the polyester resin particles contained in the obtained resin particle dispersion is also measured by the above method.

The polyester resin is obtained by a well-known manufacturing method. Specifically, for example, the polymerization temperature is set to 180 ° C. or higher and 230 ° C. or lower, the pressure in the reaction system is reduced as necessary, and the reaction is performed while removing water and alcohol generated during the condensation.
In addition, when the monomer of the raw material is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added and dissolved as a solubilizing agent. In this case, the polycondensation reaction is performed while distilling off the solubilizer. If a monomer with poor compatibility is present in the copolymerization reaction, the monomer with poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polymerized together with the main component. It is good to condense.

  Examples of the ionic surfactant include an anionic surfactant, a cationic surfactant, and an amphoteric surfactant. One type may be used alone, or two or more types may be used in combination.

Examples of the anionic surfactants include sulfate ester surfactants, sulfonate surfactants, phosphate ester surfactants, and soap surfactants.
Examples of the sulfate ester surfactant include monoalkyl sulfates such as sodium octadecyl sulfate, sodium lauryl sulfate, and potassium lauryl sulfate; alkyl polyoxyethylene sulfates such as sodium polyoxyethylene lauryl sulfate; and the like.
Examples of the sulfonate surfactant include sodium n-hexyl sulfonate, sodium 2-ethylhexyl sulfonate, sodium heptyl sulfonate, sodium n-octyl sulfonate, sodium nonyl sulfonate, sodium decyl sulfonate, and undecyl. Alkyl sulfonates such as sodium sulfonate and sodium dodecyl sulfonate; alkyl benzene sulfonates such as sodium dodecyl benzene sulfonate; alkyl naphthalene sulfonates such as sodium butyl naphthalene sulfonate; sulfosuccinates such as sodium dilauryl sulfosuccinate Salts; alkyl diphenyl ether disulfonates such as sodium dodecyl diphenyl ether disulfonate; and the like.
Examples of the phosphate ester surfactant include monoalkyl phosphates such as sodium stearyl phosphate.
Examples of the soap-based surfactant include fatty acid salts such as sodium oleate, sodium laurate, and potassium stearate.

Examples of the cationic surfactant include aliphatic quaternary ammonium salts such as lauryltrimethylammonium chloride; aromatic quaternary ammonium salts; N-acylamine salts; imidazolium salts;
Examples of amphoteric surfactants include alkylbetaines, alkylsulfobetaines, and lecithin.

  As addition amount (solid content conversion) of an ionic surfactant, 0.1 mass part or more and 25 mass parts or less are mentioned, for example with respect to 100 mass parts of polyester resins, and 1 mass part or more and 15 mass parts or less are more preferable. 2 parts by mass or more and 10 parts by mass or less are more preferable. When the addition amount of the ionic surfactant is within the above range, resin particles having a narrow particle size distribution can be obtained and the molecular weight of the polyester resin can be controlled as compared with the case where the amount is less than the above range. Further, since the addition amount of the ionic surfactant is in the above range, excessive plasticization of the polyester resin by the surfactant is suppressed as compared with the case where the addition amount is larger than the above range, and the strength and thermal characteristics of the resin are reduced. Deterioration is suppressed.

  The melt-kneading temperature in the melt-kneading step (the temperature from the block 12A to the block 12B of the barrel 12 in FIG. 1) is set for each block according to the type and amount of the polyester resin and ionic surfactant used. For example, the melt kneading temperature in the block 12A is, for example, 120 ° C. or less, and preferably in the range of 80 ° C. or more and 120 ° C. or less. Further, the melt kneading temperature in the block 12B is preferably 100 ° C. or less, and preferably 80 ° C. or more and 100 ° C. or less, from the viewpoint of preventing the aqueous medium added from the liquid addition port 16A from bouncing in the block 12C and deteriorating the emulsification properties. The range of is more preferable.

  In the present embodiment, both the polyester resin and the ionic surfactant are injected from the injection nozzle 14, but the present invention is not limited to this. Specifically, for example, the polyester resin and the ionic surfactant may be injected from separate injection ports, and the ionic surfactant may be added to the melted polyester resin. In that case, the ionic surfactant may be added before the alkali agent is added to the polyester resin. However, a part of the ionic surfactant may be added to the polyester resin before the addition of the alkali agent. For example, another part of the ionic surfactant may be added to the polyester resin in the addition step. .

-Addition process-
In the addition step, an alkali agent and an aqueous medium are added to the mixture of the polyester resin melted and kneaded in the melt-kneading step and the ionic surfactant. Specifically, for example, a mixed solution of an alkaline agent and an aqueous medium is introduced into the liquid addition port 16A of the screw extruder 11 shown in FIG. 1, and an aqueous solution for phase transition is introduced into the liquid addition port 16B and the liquid addition port 16C. Insert the media. As a result, the mixed solution of the alkali agent and the aqueous medium is added to the melt-kneaded product (mixture of the melt-kneaded polyester resin and the ionic surfactant) that flows in the barrel 12 while being melt-kneaded with a screw in the block 12C. In addition, an aqueous medium is added in block 12F and block 12I.
Hereinafter, the aqueous medium used to obtain the mixed solution with the alkaline agent (the aqueous medium introduced from the liquid addition port 16A) is referred to as “first aqueous medium”, and the aqueous solution for phase transition that is added separately from the alkaline agent. The medium (the aqueous medium introduced from the liquid addition port 16B and the liquid addition port 16C) may be referred to as a “second aqueous medium”.

The mixture of the polyester resin melted and kneaded as described above and the ionic surfactant is added with an alkali agent and an aqueous medium in Block 12C, Block 12F, and Block 12I while being stirred with a screw. Then, by adding the second aqueous medium in the block 12F and the block 12I, the resin phase is discontinuously phased to cause phase transition (phase inversion emulsification occurs), and the polyester resin particles are dispersed in the aqueous medium. A liquid is obtained.
Finally, the resin particle dispersion formed by the addition of the alkaline agent and the aqueous medium is transported to the block 12J by the screw and then discharged from the discharge port 18.

The alkali agent is not particularly limited as long as it shows alkalinity, and one kind may be used alone, or two or more kinds may be used in combination.
The alkaline agent is preferably a compound having a function of enhancing the function of the ionic surfactant, and specific examples thereof include silicate, phosphate, carbonate and the like.
Specific examples of the silicate include sodium orthosilicate, sodium metasilicate, sodium sesquisilicate, and a mixture thereof.
Specific examples of the phosphate include sodium tripolyphosphate, sodium pyrophosphate, potassium pyrophosphate, sodium tetraphosphate, sodium hexametaphosphate, and the like.
Specific examples of the carbonate include sodium carbonate, sodium hydrogen carbonate, sodium sesquicarbonate and the like.

Among these, the alkali agent is preferably a silicate, a phosphate, or a carbonate from the viewpoint of activating the ionic surfactant and suppressing a decrease in the weight average molecular weight of the polyester resin. Phosphate is more preferred and silicate is even more preferred. Of the silicates, orthosilicate is most preferred.
Moreover, as a combination of the ionic surfactant used in the melt-kneading step and the alkali agent used in the addition step, from the viewpoint of activating the ionic surfactant and suppressing the decrease in the weight average molecular weight of the polyester resin. A combination of sodium polyoxyethylene lauryl sulfate and sodium orthosilicate, a combination of sodium polyoxyethylene lauryl sulfate and sodium metasilicate, a combination of sodium dodecyl diphenyl ether disulfonate and sodium orthosilicate, and preferably sodium polyoxyethylene lauryl sulfate And a combination of sodium orthosilicate is more preferable. As the number of polyoxyethylene groups, the emulsifiability changes depending on the compatibility with the resin, so that the number of polyoxyethylene groups can be arbitrarily selected.

  The alkaline agent can be added alone, but for the purpose of mitigating local uneven distribution and a small amount compared to the flowing resin mixture, the alkaline agent is mixed in advance with the first aqueous medium. It is preferable to add to the mixture of the melt-kneaded polyester resin and the ionic surfactant in the state of a mixed solution of the first aqueous medium. The first aqueous medium may be the same as the second aqueous medium, or may be different from the second aqueous medium.

  The amount of alkali agent added (in terms of solid content) is the amount of the actual component of the ionic surfactant (excluding the solvent, etc.) from the viewpoint of enhancing the emulsifying function of the ionic surfactant and making it easier to form resin particles. , Unit: mol), the molar ratio is preferably 0.4 times or more and 6.0 times or less, and more preferably 0.6 times or more and 4.5 times or less.

  The aqueous medium is not particularly limited as long as it contains water, and specific examples include water such as distilled water and ion exchange water; alcohols; and the like. These may be used individually by 1 type and may use 2 or more types together.

  The addition amount of the aqueous medium (total addition amount of the first aqueous medium and the second aqueous medium) is 30 parts by mass or more and 300 parts by mass with respect to 100 parts by mass of the polyester resin from the viewpoint of forming resin particles by phase inversion emulsification. The amount is preferably not more than part by mass, more preferably not less than 30 parts by mass and not more than 200 parts by mass.

  The temperature of the mixture in the addition step (the temperature from block 12C to block 12I of barrel 12 in FIG. 1) is not particularly limited, but the aqueous medium added from liquid addition port 16A, liquid addition port B, and liquid addition port 16C is not limited. From the viewpoint of suppressing bumping, 100 ° C. or lower is preferable. Moreover, it is preferable that the temperature of block 12J shall be below the glass transition temperature of a polyester resin from a viewpoint which suppresses that the resin particle dispersion obtained by phase inversion rephases.

In this embodiment, the mixed solution of the alkaline agent and the first aqueous medium is added from the liquid addition port 16A, and the second aqueous medium is added from the liquid addition port 16B and the liquid addition port 16C. It is not restricted to this form. Specifically, for example, only the alkaline agent may be added from the liquid addition port 16A, and all the aqueous medium may be added from at least one of the liquid addition port 16B and the liquid addition port 16C.
Further, an addition port other than the liquid addition port 16A, the liquid addition port 16B, and the liquid addition port 16C is further provided in the addition portion SB (that is, the block 12C to the block 12I) of the barrel 12, and a small amount of the aqueous medium is divided into multiple stages. It may be in the form of being added one by one.
Alternatively, a part of the ionic surfactant may be charged into the injection nozzle 14 and an alkali agent previously dissolved in the other part of the ionic surfactant may be added from the liquid addition port 16A. Good.

As described above, in this embodiment, the resin particle dispersion is manufactured through the melt-kneading step and the adding step.
In addition, although the manufacturing method of the resin particle dispersion in the form which applied the fluid addition method was demonstrated, this embodiment is not restricted to this, Even if a melt-kneading process and an addition process are performed by a batch type (what is called a batch type). Good.

-Resin particle dispersion-
In the method for producing a resin particle dispersion in this embodiment, since the weight average molecular weight of the polyester resin is controlled as described above, a resin particle dispersion in which resin particles having a large weight average molecular weight are dispersed in an aqueous medium is obtained. Specifically, the weight average molecular weight of the resin particles in the resin particle dispersion obtained in the present embodiment includes, for example, a range of 35,000 to 120,000, and more preferably 38,000 to 100,000.

The volume average particle size of the resin particles in the resin particle dispersion obtained in the present embodiment is preferably 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, and more preferably 0.1 μm or more. More preferably, it is 0.6 μm or less.
The volume average particle size of the resin particles is determined by dividing the particle size range (channel) by using the particle size distribution obtained by measurement with a laser diffraction particle size distribution measuring device (for example, LS13 320 manufactured by Beckman Coulter, Inc.). On the other hand, the cumulative distribution is drawn from the small particle size side with respect to the volume, and the particle size that becomes 50% cumulative with respect to all particles is measured as the volume average particle size D50v. The volume average particle size of particles in other dispersions is also measured in the same manner.

The volume average particle size distribution index (GSDv) of the resin particles in the resin particle dispersion obtained in the present embodiment includes, for example, less than 1.30, and preferably less than 1.25.
The volume average particle size distribution index (GSDv) is obtained by subtracting the cumulative distribution from the small particle size side for the volume of the divided particle size range (channel) in the particle size distribution obtained by the measurement of the volume average particle size. When the particle diameter that is 16% cumulative is defined as the volume average particle diameter D16v, and the particle diameter that is 84% cumulative is defined as the volume average particle diameter D84v, the following expression is obtained.
Formula: Volume average particle size distribution index (GSDv) = (D84v / D16v) ^1/2

  As content of the resin particle contained in the resin particle dispersion liquid obtained by this embodiment, 5 mass% or more and 50 mass% or less are preferable with respect to the whole resin particle dispersion liquid, for example, and 10 mass% or more and 40 mass% are preferable. The following is more preferable.

  Examples of the use of the resin particle dispersion obtained by the method for producing a resin particle dispersion in the present embodiment include a carrier such as a medicine in addition to toner particles described later.

<Method for producing toner particles>
The toner particle manufacturing method according to the present embodiment includes a resin particle dispersion manufacturing step of manufacturing a resin particle dispersion in which polyester resin particles are dispersed in an aqueous medium by the above-described resin particle dispersion manufacturing method, and the resin particles. In the dispersion, the polyester resin particles are aggregated to form aggregated particles containing the polyester resin particles, and the aggregated particle dispersion step in which the aggregated particles are dispersed in the aqueous medium is heated. And fusing and coalescing the agglomerated particles to form toner particles.

Details of each step will be described below.
In the following description, a method of obtaining toner particles containing a colorant and a release agent will be described. However, the colorant and the release agent are used as necessary. Of course, you may use other additives other than a coloring agent and a mold release agent.

-Dispersion preparation process-
First, together with a resin particle dispersion in which resin particles serving as a binder resin are dispersed, for example, a colorant particle dispersion in which colorant particles are dispersed and a release agent particle dispersion in which release agent particles are dispersed are prepared. To do.

  Regarding the volume average particle diameter of the particles in the resin particle dispersion, the dispersion medium, the dispersion method, and the content of the particles, the colorant particles dispersed in the colorant particle dispersion and the release agent particle dispersion are dispersed. The same applies to the release agent particles.

  As a method for dispersing the particles in the colorant particle dispersion and the release agent particle dispersion, a general dispersion method such as a rotary shearing homogenizer, a ball mill having media, a sand mill, or a dyno mill may be used.

-Aggregated particle formation process-
Next, the colorant particle dispersion and the release agent particle dispersion are mixed together with the resin particle dispersion.
Then, in the mixed dispersion, resin particles, colorant particles, and release agent particles are hetero-aggregated to have resin particles, colorant particles, and release agent particles having a diameter close to the diameter of the target toner particles. Aggregated particles are formed.

Specifically, for example, the flocculant is added to the mixed dispersion, and the pH of the mixed dispersion is adjusted to acidic (for example, the pH is 2 or more and 5 or less), and a dispersion stabilizer is added as necessary. The resin particles are heated to a glass transition temperature (specifically, for example, the glass transition temperature of the resin particles −30 ° C. or more and the glass transition temperature −10 ° C. or less), and the particles dispersed in the mixed dispersion liquid are aggregated. , Forming aggregated particles.
In the agglomerated particle forming step, for example, the aggregating agent is added at room temperature (for example, 25 ° C.) while stirring the mixed dispersion with a rotary shearing homogenizer, and the pH of the mixed dispersion is acidic (for example, the pH is 2 or more and 5 or less). ), And after adding a dispersion stabilizer as necessary, the heating may be performed.

  Examples of the flocculant include a surfactant having a polarity opposite to that of the surfactant used as the dispersant added to the mixed dispersion, an inorganic metal salt, and a divalent or higher-valent metal complex. In particular, when a metal complex is used as the flocculant, the amount of the surfactant used is reduced, and the charging characteristics are improved.

  Examples of inorganic metal salts include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and inorganic substances such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Examples thereof include metal salt polymers.

-Fusion / unification process-
Next, the aggregated particle dispersion in which the aggregated particles are dispersed is heated to, for example, a glass transition temperature or higher of the resin particles (for example, a temperature of 10 to 30 ° C. higher than the glass transition temperature of the resin particles). Are fused and united to form toner particles.

Through the above steps, toner particles are obtained.
In addition, after obtaining the aggregated particle dispersion liquid in which the aggregated particles are dispersed, the aggregated particle dispersion liquid and the resin particle dispersion liquid in which the resin particles are dispersed are further mixed, and the resin particles are further added to the surface of the aggregated particles. A process of aggregating to adhere to form second aggregated particles, and heating the second aggregated particle dispersion in which the second aggregated particles are dispersed to fuse and coalesce the second aggregated particles. The toner particles may be manufactured through a step of forming toner particles having a core / shell structure.

Here, after completion of the fusion / unification process, toner particles formed in the solution are dried through a known washing process, solid-liquid separation process, and drying process to obtain toner particles.
In the washing step, it is preferable to sufficiently carry out substitution washing with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, etc. are preferably performed from the viewpoint of productivity. Also, the drying process is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying, or the like is preferably performed.

As described above, in the present embodiment, toner particles are manufactured through the resin particle dispersion manufacturing process, the aggregated particle forming process, and the fusing / merging process.
Hereinafter, a colorant, a release agent, and other additives used as necessary for the production of toner particles will be described.

-Colorant-
Examples of the colorant include carbon black, chrome yellow, hansa yellow, benzidine yellow, slen yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliant carmine 3B, and brilliant. Carmine 6B, Dupont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Pigment Red, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Phthalocyanine Green, Various pigments such as malachite green oxalate, or acridine, xanthene, Dyes such as benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, phthalocyanine, aniline black, polymethine, triphenylmethane, diphenylmethane, and thiazole Etc.
A colorant may be used individually by 1 type and may use 2 or more types together.

  As the colorant, a surface-treated colorant may be used as necessary, or it may be used in combination with a dispersant. A plurality of colorants may be used in combination.

  The content of the colorant is, for example, preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 15% by mass or less with respect to the entire toner particles.

-Release agent-
Examples of mold release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; ester waxes such as fatty acid esters and montanic acid esters And so on. The release agent is not limited to this.

The melting temperature of the release agent is preferably 50 ° C. or higher and 110 ° C. or lower, and more preferably 60 ° C. or higher and 100 ° C. or lower.
The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) according to the “melting peak temperature” described in JIS K-1987 “Method for measuring the transition temperature of plastics”.

  The content of the release agent is, for example, preferably 1% by mass to 20% by mass and more preferably 5% by mass to 15% by mass with respect to the entire toner particles.

-Other additives-
Examples of other additives include known additives such as a magnetic material, a charge control agent, and inorganic powder. These additives are contained in the toner particles as internal additives.

  Hereinafter, although an embodiment explains this embodiment in detail, this embodiment is not limited to these examples at all. In the following description, “part” and “%” are all based on mass unless otherwise specified.

[Production of resin particle dispersion]
Example 1
A resin particle dispersion was produced using a screw extruder 11 shown in FIG. Specifically, a polyester resin and an ionic surfactant are injected into the injection nozzle 14, an alkali agent and a first aqueous medium are introduced into the liquid addition port 16A, and a second aqueous medium is introduced into the liquid addition port 16B and the liquid addition port 16C. .
The conditions in the melt-kneading step and the addition step are as follows: the screw rotation speed is set to 400 rpm, the polyester resin and the ionic surfactant are introduced into the injection nozzle 14 at a flow rate of 7.5 kg / hour, and the melt-kneading temperature: 98 ° C. The temperature of the mixture in the addition step was 99 ° C. The alkaline agent is preliminarily dissolved in the first aqueous medium to prepare an aqueous solution having a specified concentration, and then added from the liquid addition port 16A (installed in the block 12C), and a part of the second aqueous medium is liquid addition port 16B ( From block 12F). The remaining second aqueous medium is introduced from the liquid addition port 16C (installed in the block 12I), but the second aqueous medium added from the liquid addition port 16B and the second aqueous medium added from the liquid addition port 16C. The addition flow rate of the medium was adjusted each time so that the emulsion (resin particle dispersion) flows out from the discharge port 18 at a constant flow rate. The screw configuration of the melt kneading part SA and the addition part SB is such that the resin is discharged without being emulsified if it is transported too early, and if the shear mixing due to residence is too strong, the emulsion is pulsated and discharged due to bumping phenomenon due to heat generation. Therefore, fine adjustment of the configuration was performed as appropriate. Furthermore, when bumping was severe, adjustments such as lowering the control temperature of each block in the barrel 12 were performed.

In addition, the types of input materials are as follows. However, ion-exchanged water was used for both the first aqueous medium and the second aqueous medium. In addition, Table 1 shows the amount of added materials. Table 1 also shows the molar ratio of the added alkali agent to the actual component amount of the ionic surfactant (amount excluding the solvent, unit: mol).
Polyester resin 1 (synthetic product; weight average molecular weight: 89000, crosslinking component having 3 or more functional groups: trimellitic acid, dicarboxylic acid component: terephthalic acid and dodecenyl succinic acid comonomer, diol component: bisphenol A ethylene oxide 2-mole adduct )
-Ionic surfactant 1 ("Manufacturer: Shin Nippon Rika Co., Ltd., trade name: Sinoline SPE-1350, compound name: sodium lauryl sulfate" with ion-exchanged water as a solvent so that the solid content is 25% by mass. Diluted)
Alkaline agent 1 ("Manufacturer: Strem Chemicals, Inc., compound name: sodium orthosilicate" diluted with ion-exchanged water as the first aqueous medium so that the solid content is 25% by mass)

(Example 2)
In Example 1, when the resin powder was introduced from the injection nozzle 14, the ionic surfactant was quantitatively supplied from the liquid injection port 14 </ b> A laid at one end of the injection nozzle 14. Further, the alkali agent and the first aqueous medium were charged from the liquid addition port 16A. The second aqueous medium was divided and added from the liquid addition port 16B and the liquid addition port 16C. Except for these, kneading was performed using the same apparatus as in Example 1 to obtain a resin particle dispersion.
In addition, the type of the input material is the same as that in the first embodiment. The amount of added material is shown in Table 1.

(Example 3 and Example 4)
A resin particle dispersion was obtained in the same manner as in Example 2 except that the addition amounts of the ionic surfactant and the alkali agent were changed as shown in Table 1 among the charged materials.

(Example 5)
Among the charged materials, the type of the alkaline agent was changed to the following alkaline agent 2, and the resin particle dispersion was obtained in the same manner as in Example 2 except that the addition amount of the alkaline agent was changed as shown in Table 1. .
Alkaline agent 2 ("Manufacturer: Wako Pure Chemical Industries, Compound name: Sodium hydroxide" diluted with ion-exchanged water as the first aqueous medium so that the solid content is 50% by mass)

(Comparative Examples 1 to 3)
When the resin powder was introduced from the injection nozzle 14, the alkaline agent and the first aqueous medium were quantitatively supplied from the liquid injection port 14 </ b> A laid at one end of the injection nozzle 14. The ionic surfactant solution was charged from the liquid addition port 16A. The second aqueous medium was added separately from the liquid addition port 16B and the liquid addition port 16C. Except for these, kneading was performed using the same apparatus as in Example 1 to obtain a resin particle dispersion.
The conditions in the melt-kneading step and the adding step were as follows: melt-kneading temperature: 99 ° C., temperature of the polyester resin in the adding step: 97 ° C. Other than that, it adjusted similarly to Example 1. FIG.
Table 1 shows the types and amounts of the added materials.

(Comparative Example 3)
A resin particle dispersion was produced in the same manner as in Comparative Example 1 except that the type of the alkaline agent was changed to the alkaline agent 1 and the addition amount of the alkaline agent was changed as shown in Table 1 among the charged materials. .
(Comparative Example 4)
Among the charged materials, the type of ionic surfactant is changed to the following ionic surfactant 2, and the addition amount of each of the ionic surfactant and alkaline agent is changed as shown in Table 1 to disperse the resin particles. A liquid was produced.
-Ionic surfactant 2 ("Manufacturer: Dow Chemical, trade name: Dowfax 2AI, compound name: alkyldiphenyl oxide disulfonate" diluted with ion-exchanged water as a solvent so that the solid content is 25% by mass )

[Evaluation of resin particle dispersion]
(Evaluation of weight average molecular weight of resin particles)
The polyester resin particles contained in the resin particle dispersions obtained in the above Examples and Comparative Examples were measured by the above method. The results are shown in Table 1.

(Evaluation of particle size distribution of resin particles)
About the resin particle dispersion liquid obtained by the said Example and comparative example, the particle size distribution of the resin particle was evaluated on the following references | standards. The following particle size distribution and volume average particle size distribution index were measured by the above methods. The evaluation results are shown in Table 1.

-Evaluation criteria-
G1: The volume average particle size distribution index was less than 1.25 G2: The volume average particle size distribution index was 1.25 or more and less than 1.30 G3: A plurality of maximum peaks in the particle size distribution existed G4: Emulsified Didn't exist

  In addition, the addition amount (part by mass) of the ionic surfactant shown in Table 1 is an amount that does not include the solvent (ion-exchanged water). Moreover, the addition amount (mol) of the alkaline agent shown in Table 1 is the actual component amount of the alkaline agent that does not contain the first aqueous medium (ion-exchanged water). Further, the molar ratio of the alkaline agent shown in Table 1 is the amount of the alkaline agent added to the actual component amount of the ionic surfactant (amount excluding the solvent, unit: mol) (the alkali not including the first aqueous medium). It is the ratio (molar ratio) of the actual component amount of the agent alone, unit: mol). Moreover, the addition amount (part by mass) of the aqueous medium shown in Table 1 is the total addition amount of the first aqueous medium and the second aqueous medium.

  From the above results, it can be seen that the weight average molecular weight in the polyester resin is controlled in this example as compared with the comparative example.

11 Screw Extruder 12 Barrel 12A-12J Block 14 Injection Nozzle 16A-16C Liquid Addition Port 18 Discharge Port SA Melting and Kneading Section SB Addition Section SC Discharge Section

Claims (7)

A melt-kneading step of melt-kneading a mixture of the polyester resin and the ionic surfactant;
An addition step of adding an alkali agent and an aqueous medium to the melt-kneaded mixture to obtain a resin particle dispersion in which the polyester resin particles are dispersed in the aqueous medium;
Have
The amount of the ionic surfactant is state, and are less than 25 parts by mass or more 0.1 part by weight relative to the polyester resin 100 parts by weight,
The polyester resin has a weight average molecular weight of 40,000 or more and 100,000 or less,
The polyester resin is crosslinked with a crosslinking component having 3 or more functional groups,
The alkali agent is a method for producing a resin particle dispersion containing a silicate .   The method for producing a resin particle dispersion according to claim 1, wherein the melt kneading in the melt kneading step is 120 ° C. or lower.   The method for producing a resin particle dispersion according to claim 1, wherein the silicate is orthosilicate. The resin particle according to any one of claims 1 to 3 , wherein an addition amount of the ionic surfactant is 0.1 parts by mass or more and 4.0 parts by mass or less with respect to 100 parts by mass of the polyester resin. A method for producing a dispersion. 5. The method for producing a resin particle dispersion according to claim 4 , wherein the addition amount of the alkaline agent is 0.4 to 10.0 times in molar ratio with respect to the addition amount of the ionic surfactant.   In the melt-kneading step and the adding step, the mixture is melt-kneaded while flowing the mixture from one end to the other end in the cylindrical body, and the alkali agent and the aqueous medium are added to the melt-kneaded mixture. The manufacturing method of the resin particle dispersion liquid of any one of Claims 1-5 which is a process to perform. A resin particle dispersion production process for producing a resin particle dispersion in which polyester resin particles are dispersed in an aqueous medium by the method for producing a resin particle dispersion according to any one of claims 1 to 6 .
In the resin particle dispersion, the polyester resin particles are aggregated to form aggregated particles including the polyester resin particles, and an aggregated particle forming step;
A fusion / union step of heating the aggregated particle dispersion in which the aggregated particles are dispersed in the aqueous medium, and fusing and coalescing the aggregated particles to form toner particles;
A method for producing toner particles having: